The Laboratory of Neurobiology is an interdisciplinary research facility for the study of neurobiological problems, taking advantage when convenient of the rich marine fauna, both vertebrate and invertebrate, available in the littoral waters of Puerto Rico. Facilities include: several electrophysiological set-ups, including a PDP-12 Digital Computer for data processing; two electronmicroscopes; general biochemical laboratory; photography; running sea water and holding tanks; diving facilities and two collecting boats. Ongoing research activities include: problems related to transmitter release, properties of postsynaptic muscle receptors in both vertebrates and crustacea, analysis of units in optic lobe of octopus, study of myepithelial cells in marine annelids, behavioural and neurophysiological works on sharks, etc. The Laboratory is placed under the Chancellor Office of the Medical Science Campus of the U.PR. and is opened to qualified visiting scientists.